I just recently bought some new equipment (HBM mini lathe and a 3018 cnc-machine) and wanted to do a little project to test out the 2 machines and get familiar with them.
Since I just passes 25K subs I decided to do a little giveaway to show my appreciation to all of you. I really would've never thought I would even reach 1K let alone 25K, so thank you very very much ;-)
I first tried to hold the coin down on the engraving table using double sided tape, but this didn't turn out to be a great idea because the lubricant used for the drill bit dissolved the double sided tape. In the next attempt I used 2 component epoxy glue which worked excellent. Removing the epoxy glue turned to be pretty easy. I used a 25 degree, 0.1mm tip engraving bit, they did brake from time to time but lowering the engraving speed helped a lot.
I used this model to engrave a bitcoin pattern onto a coin but you can also use the STL-file to print it out using your 3D-printer. You might have to scale it up a bit to reach to desired detail.
I tried to work as safe as possible with the mini lathe (no long sleeves, removed watch, closed safety covers, etc...) but I do realize working this close to the chuck might not be the best idea, so I wouldn't recommend you doing this.
Some of you might also note I'm "destroying" money. this was also one of my main concerns when I started this project so I did some research. This is what I found on the website of the National Bank of Belgium:
"When notes or coins are definitively withdrawn from circulation, one is not punishable. This is the case, for example, if they are incorporated into souvenirs, decorative works or works of art in such a way that they can no longer be returned to their original state."
I also send them an email just to be sure but I guess this isn't even worth their time because they just keep redirecting me to other departments and it has been a few months now since I've heard from them. but we should be good.
The model can be 3D-printed and/or engraved.
The fusion 360 source file option includes these formats:
-.zip (containing .ipt and .iam files)
Part list, schematics, code and more info about this project can be found here
Note: This is not a physical product. When you're purchasing the STL or Fusion 360 source files you will be able to download these files. A physical product will not be send to your address.
All my designs are licensed according to the CC BY-NC-ND license: https://creativecommons.org/licenses/by-nc-nd/4.0/